Rubbing or polishing machine.



No. 788,349, PATENTED FEB. 21, 1905.

0. s YARNELL. RUBBING 0R POLISHING MACHINE.

APPLICATION FILED APR. 28, 1904.

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' BY Hum/ya 11777755655 Y/IF/YELL' 70m 5% No. 783,349. PATENTED FEB. 21, 1905.

G. S. YARNELL.

RUBBING 0R POLISHING MAUHINE.

APPLIOATION FILED APR. 28, 1904.

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No. 783,349. PATENTED FEB. 21, 1905. 0. s. YARNELL.

RUBBING 0R POLISHING MACHINE.

APPLICATION IE'ILED APR. 28, '1904.

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PATENTED FEB. 21, 1905.

C. S. YARNELL. RUBBING 0R POLISHING MACHINE.

APPLICATION FILED APR. 28, 1904.

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PATENTED FEB. 21, 1905.

(LS. YARNELL. RUBBING OR POLISHING MACHINE.

Illll' APPLIGATION FILED APR. 28, 1904.

llllll E k if UNITED STATES Patented February 21, 1905.

PATENT OEEIcE.

CHARLES S. YARNELL, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO MOORE CARVING MACHINE COMPANY, OF MINNEAPOLIS, MINNE- SOTA, A CORPORATION.

RUBBING OR POLISHING MACHIN E.

SPECIFICATION forming part of Letters Patent N0. 783,349, dated February 21, 1905.

Application filed April 28, 1904. Serial No. 205,338. I

To all whom it may concern.-

Be it known that I, CHARLES S. YARNELL, of Minneapolis, in the county of Hennepin, State of Minnesota, have invented certain new and useful Improvements in Rubbing or Polishing Machines, of which the following is a specification.

This invention relates to rubbing and polishing machines designed for sandpapering or polishing surfaces of wood, although the machine is capable without reconstruction of being used for rubbing or polishing surfaces of other materials.

The present invention relates particularly to improvements in the machine shown and described in an application for Letters Pat-' cnt filed by me October 31, 1903, Serial No. 179,274.

The object of my present invention is to provide a machine of this character with two or more sanding, rubbing, or polishing belts, which may be of different degrees of fineness, with means for bringing either belt at will into contact with the surface to be rubbed or polished.

The invention consists generally in a rubbing or polishing machine provided with two or more sanding, rubbing, or polishing belts and means for bringing any one of said belts into contact with the article or material to be rubbed or polished.

The invention consists, further, in providing a machine of this character with a movable pressure plate or head adapted to be brought in contact with either of the sanding or polishing belts and to be operated to press such belt against the surface of the article or material to be rubbed or polished.

The invention consists, further, in the constructions and combinations hereinafter described, and particularly pointed out in the claims.

In the accompanying drawings, forming part of this specification, Figure 1 is a front elevation of a machine embodying my invention. Fig. 2 is a plan view of the same. Fig. 3 is an end elevation. Figs. 4, 5, and 6 are details of the pressure-plate and mechanism for shifting such plate from one belt to the other. Figs. 7 8, and 9 are details of the means for adjustably supporting the belt-supporting pulleys,

In its general features this machine is similar to that shown and described in my prior application above referred to. The present machine is, however, provided with a plurality of sanding or polishing belts, and the pressure plate or head, which is used to press the belt against the article to be polished, is capable of being shifted from one belt to the other.

In the drawings, 2 represents the frame of the machine, which is of any preferred or suitable construction. This frame carries the horizontal rails or ways 4, upon which is supported by suitable wheels 3 the worktable 3. This table may be moved forward and back by hand beneath the sanding, rubbing, or polishing belts. The rails or ways 4 and the work-table are preferably provided with means for raising or lowering them. I have not in this application shown the means for raising and lowering the rails and table; but suitable means for this purpose are shown and described in my above-named application.

Secured upon the standards 2 are the horizontal bars or beams 6, suitably secured at their ends to said standards. Upon the beams 6, preferably at one end thereof, I secure a plate 7 carrying the shaft-boxes 8, in which is mounted a driving-shaft 9, having suitable fast and loose pulleys l0 and 11. This shaft also carries two belt-pulleys 12. The plate7 is preferably rigidly secured in position. At the opposite end of the machine I provide two belt-pulleys 16, both of which are adjustably supported by means hereinafter described. Mounted upon the pulleys 12 and 16 are suitable sandpaper or other rubbing or polishing belts 25. One of these belts is preferably finer than the other.

I provide a pressure-plate 28 similar to that shown in my said former application, and this plate is supported upon a horizontal bar 26 plates 43, arranged transversely upon the machine and supported upon the beams 6. The plates 41 are free to slide in the grooves in the plates 43, and they are preferably held in position by the metal strips 42. (See Fig. 5.) Secured upon the plates 43 are the rackbars 44, and mounted upon the sliding plates 41 is a shaft 45. This shaft is provided with the pinions 46, which mesh with the teeth-of the rack-bars 44. The shaft 45 is also provided with the beveled pinion 47, and mounted upon one of the plates 41 by means of suitable standards 48 is a shaft 49, provided at one end with a beveled pinion 50, that meshes with the beveled pinion 47 on the shaft 45 and at its other end with a handwheel 52. Upon one of the plates 41, preferably the one at the center of the machine, I provide the bell-crank lever 53, carrying a counterweight 54 and connected by the link 55 with the upwardly-projecting end 56 of the lever 40. I prefer to provide a rod 56, that is secured at the upper ends of.the levers 40, thereby connecting said levers, so that they move in unison. An operating-lever 57 is secured upon one of the levers 40, (see Fig. 4,) and this lever has upon its end a pivoted catch 58, adapted to engage a stationary lug 59 on the sliding plate 41 Thelever 57 projects toward the front of the machine and is provided with a handle 60,connected by a rod 61 with the catch 58. By means of the handle the catch 58 may be released from the lug 59, and by depressing the lever 57 the operator turns the levers 40 upon their pivots and moves the plate 28 down ward, so as to press the sanding or polishing belt with any desired amount of pressure upon the article to be finished. When the polishing operation ceases, the plate 28 is raised by the lever 57 and the catch 58 is allowed to engage the lug 59. polishing belt will now be clear of the work or article beneath it, and the pressure-plate may by turning the rod 49 be moved from a position over one belt to a position overthe other. The pressure-plate may then be depressed, and this belt may be brought into contact with the article to be polished. The pressure-plate may be moved from one belt to the other as often as desired. The belt which is not engaged by the pressure-plate will not be in contact with the article to be polished, and hence'this belt will run clear of the work. The pressure-plate is always brought upon The sanding or the belt with a yielding pressure, and this plate is counterbalanced by the counterweight 54 upon the lever 53. The belt-pulleys 16 are each mounted so as .to be capable of adjustment for tightening and alining the belt. One of the pulleys 16 is mounted upon a stationary stub-shaft 63, and this shaft is secured, preferably by suitable screws 64, in a bearing 65 upon a plate 66. The plate 66 is slotted and is secured to the beams 6 by the bolts 67. A screw 68 passes through a flange upon the end of the plate 66 and engages a threaded opening in the frame of the machine. By means of this screw the plate 66 and the shaft 63 carriedthereby may be moved toward or from the driving-shaft of the machine, and thereby the belt supported upon this bearing may be adjusted. The bearing 65 is secured upon the plate 66 by means of a pivot-screw 69, and adjustingscrews 70 are arranged at the opposite ends of the bearing, and by these screws the bearing may be turned upon its pivot for the purpose of adjusting the pulley 16 and alining the belt. A suitable opening for lubricating the pulley 16 may be formed in the stationary shaft63. Forsupportingtheother belt-pulley 16 I prefer to provide a separate standard 73, (see Fig. 3,) that may be suitably connected to the standard 2. This standard carries the longitudinally-adjustable plate 76, adapted to be moved by the adjusting-screw 77 and having the bearing 78 pivoted thereon. This bearing is provided with a central pivot 79, with the locking-screws 80 and the adjustingscrews 81. By this means the bearing 78, carrying the shaft 82, upon which the other pulley 16 rotates, may be adjusted toward or from the driving-shaft or may be adjusted about its pivot for the purpose of alining the belt. By the means described both of the beltpulleys 16 may be adjusted for the purpose of putting the proper tension upon the belt and for the purpose of causing said belts to run perfectly true.

I have shown a table provided with the clamping bars 85 and with the adjustingscrews 87. Iliave also shown it provided with the handles 88. I make no claim, however, to these features of the construction.

There are a number of advantages arising from the use of a pressure-plate that is capable of being shifted from one belt to another. Where such a movable pressure device is used, pressure will be applied under the same conditions upon both belts. The time required in changing belts will be saved. As it is generally necessary or desirable to use two belts happens that where there are slight depressions in the article it is convenient for the operator to place his hand upon the flexible pressure-plate and exert an additional pressure at that point. With the shiftable pressure-plate the operator can press upon any part of the plate with his hand when the plate is being used upon either belt. If the,plate is being used upon the rear belt, the operator can reach through the front belt and place his hand upon any part of thc pressure-plate upon the rear belt. As the work-table is vertically adjustable when an article to be polished is placed thereon, the table may be adjusted so as to bring the article near to but not in contact with the belt. The pressure-plate is then brought within the coarser belt, and this plate is depressed and the sanding or polishing surface of the belt is brought upon the article. This may be operated as long as desired, and then the plate may be lifted and moved into the other belt. The plate may be again depressed, and the second belt will then be brought in contact with the article.

\Vhile I have shown and described two belts, it will be understood that more than two may be employed, if desired.

I claim as my invention* 1. The combination, in a machine of the class described, with a suitable work-support, of a plurality of sanding, rubbing or polishing belts, means for driving said belts, and means arranged within said belts for bringing any one of said belts in contact with an article upon said work-support.

2. The combination, in a machine of the class described, with a suitable Work-support, of a plurality of sanding, rubbing or polishing belts, means for driving said belts, and meanscapable of being shifted from one belt to the other forbringing any one of said belts in contact with an article upon said work-support.

3. The combination, in a machine of the class described, with a suitable work-support,

of a plurality of sanding, rubbing or polishing belts, means for driving said belts, apressure plate arranged within said belts and adapted to be shifted from one belt to another, and means for depressing said plate.

4. The combination, in a machine of the class described, with a suitable work-support, of a plurality of sanding, rubbing or polishing belts, means for driving said belts, a pressure-plate arranged within said "belts, transverse slides, means upon said slides for supporting said pressure-plate, means for moving said slides and thereby shifting said plate from one belt to another, and means for depressing said plate.

5. The combination, in a machine of the class described, with a plurality of sanding, rubbing or polishing belts arranged parallel to each other, of a driving-shaft provided with a pulley for each of said belts, an independent adjustable pulley for supporting the opposite end of each of said belts, and a pressure-plate within said belts for bringing said belts in contact with an article upon said support.

6. The combination, in a machine of the class described, with a suitable work-support, of a pair of polishing-belts arranged in proximity to said work-support, a driving-shaft provided with a pulley for each of said belts, a pulley supporting the opposite end of each of said belts, and an independent longitudinally-adjustable and pivotally-supported plate supporting each of said pulleys, substantially as described.

7. The combination, in a machine of the class described, with a suitable Work-support, of a plurality of sanding, rubbing or polishing belts, means for driving the said belts, and means arranged within said belts for applying pressure separately to said several belts, to bringany one thereof in contact with an article upon said work-support.

In witness whereof I have hereunto set my hand this 23d day of April, 1904:.

CHARLES S. YARNELL.

In presence of"- A. 0. PAUL, C. G. HANSON. 

